Files
2026-01-18 21:54:08 +01:00

108 lines
2.6 KiB
Go

package app
import (
"encoding/base64"
"encoding/json"
"fmt"
"mime"
"net/http"
"os"
"path/filepath"
"github.com/skidoodle/safebin/internal/crypto"
"go.etcd.io/bbolt"
)
func (app *App) HandleGetFile(writer http.ResponseWriter, request *http.Request) {
slug := request.PathValue("slug")
if len(slug) < SlugLength {
app.SendError(writer, request, http.StatusBadRequest)
return
}
keyBase64 := slug[:SlugLength]
ext := slug[SlugLength:]
key, err := base64.RawURLEncoding.DecodeString(keyBase64)
if err != nil || len(key) != KeyLength {
app.SendError(writer, request, http.StatusUnauthorized)
return
}
id := crypto.GetID(key, ext)
var meta FileMeta
err = app.DB.View(func(tx *bbolt.Tx) error {
b := tx.Bucket([]byte(DBBucketName))
if b == nil {
return fmt.Errorf("bucket not found")
}
data := b.Get([]byte(id))
if data == nil {
return fmt.Errorf("file not found")
}
return json.Unmarshal(data, &meta)
})
if err != nil {
app.SendError(writer, request, http.StatusNotFound)
return
}
path := filepath.Join(app.Conf.StorageDir, id)
info, err := os.Stat(path)
if err != nil {
app.SendError(writer, request, http.StatusNotFound)
return
}
if info.Size() != meta.Size {
app.Logger.Error("Integrity check failed: disk size mismatch",
"id", id,
"disk_bytes", info.Size(),
"expected_bytes", meta.Size,
)
app.SendError(writer, request, http.StatusInternalServerError)
return
}
file, err := os.Open(path)
if err != nil {
app.Logger.Error("Failed to open file", "path", path, "err", err)
app.SendError(writer, request, http.StatusInternalServerError)
return
}
defer func() {
if closeErr := file.Close(); closeErr != nil {
app.Logger.Error("Failed to close file", "err", closeErr)
}
}()
streamer, err := crypto.NewGCMStreamer(key)
if err != nil {
app.Logger.Error("Failed to create crypto streamer", "err", err)
app.SendError(writer, request, http.StatusInternalServerError)
return
}
decryptor := crypto.NewDecryptor(file, streamer.AEAD, info.Size())
contentType := mime.TypeByExtension(ext)
if contentType == "" {
contentType = "application/octet-stream"
}
csp := "default-src 'none'; img-src 'self' data:; media-src 'self' data:; " +
"style-src 'unsafe-inline'; sandbox allow-forms allow-scripts allow-downloads allow-same-origin"
writer.Header().Set("Content-Type", contentType)
writer.Header().Set("Content-Security-Policy", csp)
writer.Header().Set("X-Content-Type-Options", "nosniff")
writer.Header().Set("Content-Disposition", fmt.Sprintf("inline; filename=%q", slug))
http.ServeContent(writer, request, slug, info.ModTime(), decryptor)
}